Even though current technologies of fiber laser have made significant progress toward achieving a compact and reliable fiber laser system providing high quality output laser with ever increasing output energy, however those of ordinary skill in the art are still confronted with technical limitations and difficulties. Specifically, in a fiber laser system implemented with the Chirped Pulse Amplification (CPA) for short pulse high power laser amplifier, the fiber laser systems are still limited by the technical difficulties that 1 mJ high energy femtosecond fiber laser requires multiple improvements in terms of fiber design, high power amplification, nonlinear effects mitigation, and stretching and compression operations. There is a first challenge of the nonlinear effects. When the peak power goes up to 100 kW, strong nonlinear effects such as self phase modulation (SPM) and stimulated Raman scattering (SRS) cause more serious problems in depleting signal power in the high power fiber laser, even though a large mode area (LMA) fiber be used to reduce SRS/SPM and increase saturation power. Then, there is another challenge of a third order dispersion (TOD). Due to a higher stretching ratio involves in the chirped pulse amplification, higher order dispersion such as TOD has significant impact on the pulse quality and the pulse faces a challenge to compress efficiently below 200 fs after amplification. Thus the third order dispersion (TOD) limits the scalability of the laser systems. Also, there is another challenge due to a lower extraction. The Yb-doped fibers are low in extracting more power out of fiber. Higher doping concentration has to be used for the fiber laser. Furthermore, there is a challenge of configuring the compression stage due to longer stretched pulses (a few hundreds ps-10 ns). All these challenges require new and improved fiber laser systems to reliably and practically generate the femtosecond laser at an energy level substantially near a one-mJ level.
Therefore, a need still exists in the art of fiber laser design and manufacture to provide a new and improved configuration and method to provide fiber laser to compensate the dispersion generated in the laser system due to the TOD effects such that the above-discussed difficulty may be resolved.